1. 名词单复数变形
以sis结尾的单数名词变复数时，变成ses，这种复数形式与该动词的三单拼写形式是一样的。
analysis analyses
basis bases
crisis crises
emphasis emphases
以ium结尾的名词变复数时会变成ia
bacterium bacteria
medium media
stadium stadia/stadiums
datum data
以on结尾的变为a
phenomenon phenomena
criterion criteria
2. 动词变名词
变形时原词也发生转变
explain explanation
pronounce pronunciation
repeat repetition
choose choice
serve service
compare comparison
lose loss
sell sale
believe belief
relieve relief
加t构成名词
complain complaint
weigh weight
pursue pursuit
high height
以d／de/t 结尾的变成sion
decide decision
explode explosion
conclude conclusion
include inclusion
expand expansion
provide provision
invade invasion
collide collision
persuade persuasion
admit admission
submit submission
permit permission
以ly结尾的变成cation
simply simplication
imply implication
apply application
identify identification
purify purification
classfy classification
modify modification
clarify clarification
qualify qualification
justify justification
以双唇音m(e)/b(e)结尾的变为ption
consume consumption
assume assumption
subscribe subscription
describe description
absorb absorption
以lve结尾的变成lution
solve solution
resolve resolution
evolve evolution
dissolve dissolution
3.形容词变名词
anxious anxiety
curious curiosity
poor poverty
various variety
cruel cruelty
generous generosity
4. 表示自然、国际、社会、工农商业等等高大上的名词变形容词，经常加al
nature natural
nation national
society social
industry industrial
agriculture agricultural
commerce commercial
5．高中阶段常考的几个名词形式：＂永远＂的不可数名词：equipment, furniture, information．常用复数的名词：surroundings, belongings, possessions
